This invention relates to photodetector heat sink mounting structure, and more particularly to heat sink mounting structure for conducting heat from an external source to the photocathode of a photodetector to reduce the warm up time of the photodetector in order to temperature stabilize the photodetector and to maintain the temperature stabilization.
One of the problems encountered in employing photodetector tubes resides in the fact that the photodetector tubes are temperature sensitive. Therefore, their output for a given amount of illumination changes with temperature. The photodetector is most susceptible to such temperature variation from the time the phototube is turned on until it heats up to an operating temperature and becomes temperature stabilized. For some vacuum photodiodes employing rare earth photocathodes, the warm up time may require 4 to 5 hours. Of course, measurements made during this period would be subject to considerable drift due to different operating temperatures. The delay in making analytical measurements thus becomes timeconsuming and costly.
Separate heat sources could be supplied, specifically for the purpose of heating up the photodetector but this is a costly procedure requiring extra elements and heating sources. A better solution in accordance with the present invention is to utilize an already existing heat source which requires no additional heating elements and to use the heat from such a source for the purpose of heating up the photodetector. Accordingly, it is an object of this invention to provide a method of heating a photodetector which requires no additional heating sources but utilizes heat sources which are available in the proximity of the photodetector in a simple and efficient manner.
Another object of this invention is to provide a relatively inexpensive and simple structure for heating a photodetector to more quickly stabilize its operating temperature.